Grinding machine



March 27, 1945.' w. A. sHANLEY GRINDING MACHINE 5 Shets-Sheet 1 Filed sept". A 1, 1942 Mafch217,1945. w. A. SHANLEY Y .2,372,341

GRINDING MACHINE Filed sept. 1', 1942 5-shee1-s-vsheet 3 Xm ,y

March 27, 1945. w. A. SHANLEY GRINDING MACHINE Filed Sept. l, 1942 5 Sheets-Sheet 4 /flz 4March 27, 1945. WjASHANLEy 2,372,341

GRINDING MPCHIIIE Filed Sept.l l, 1942 5 Sheets-Sheet 5 I- lilll-Ulllll 256 illy-#Inf Invenof',

Patented Mar. 27, 1945 UNITED STATES PATENT y 'GRINDING MACHINE Walter A. Shanley, Boston, Mass. y y i t 'n Application September 1, 1942, SeriallNo.-456,855-

8 Claims. .(01. 51-241-)- support at the location where a grinding operation is to-be performed; The4 grinding tool is power driven and is caused to traverse the surface which is'being ground either automatically or bvmanual operation. The invention has special utility for'grindlng a wide'variety of valves and their seats and is particularly advantageous for servicing the larger -typesV of valves suchr as are found on ocean-going craft, rfor example.

However, the numerousfeaturesl of thev invention,A as a whole erv in` part, are applicable and usable in connection. with practically everyy ccnceivable type of rotary grinding 'operation'.

universality of grinding; vfunctionsy possible ot ac'- complishment with the mechanism of the invention.

The mentioned'objects andresults may `be attained with, thev mechanism-now tobe described in detail in connection with the accompanying drawingsin which f Figure 1 shows a. larga gate valve, .casing in medial; vertical seotionhaving-my' grinding, mechanism mounted thereonzwitlr the grinding tool in valve-seat-.grinding positicn; y

FigureiZ; shows alarga; sizedlsl; valve casing, in medial verticalsectionlhavingmv grindlngfmechanism. thereon in; position. totv grind. its valvaseatr Figura is.: aA .side .elevaticniof a. frame support mounting, mv-l sinding, mechanism and a gate valvein. valvel grinding; relation; the, valve being It is amo-ng the vobjects of the invention to pro- ,Y

can traversev the circle of a valve seat or valve,

slowly with manual Afeed of the tool around the circle, or power driven at any predetermined suitable speed.

A further feature is that` the tool reciprocates transversely of the surface. which is being ground simultaneously with planetarytravel.

Still another feature resides in a radially adjustable plural roller mounting of the rotating carrier of the power driven'grinding tool thereby to permit adjustmentl of the-carrier relative to a iix-ed vtubular axle, and leaving the axle free to serve as a chuckfor. mounting .stem-type valves in position to be ground, or as a hollow tube guiding supportfor the il'exible shaft of the grinding tool when ythe power unit is mounted,"rela' tive to the location of; the grinding tool, at the remote `side of the carrier. l

Additional features involve the various provisions for angular adjust-mentsV andsettings of the carrier, the power unit, and the reciprocating carriagewhich mounts rotatably thesis-iii end portion of the tool shaft, each contributing to the inmedial verticalsentieri;Y I

Figure. 4 isa side elevation orgfgrniding: mechanism embodyingfeatures. or the invention and showing a stem. type oi.' plug valvein'positionto be ground.

Figure 5, is.. a detail-crossfsection on line 5-5 of Figure 4 onalarger scale; f

Figure 6 is a, detail sectional,view on-l line 6.-,6 of Figure All;A n p Figure- 7, is. a medial, vr='r.tical. section.r through my planetary carrier audits fixedtubular axis;

Figure 3 is a. sectional viewon. line 8-8 of Figure '7;

Figure 9 is; ainersnecti-.vefviewot the upper jaw ofthe axle clamp ofEiguresf 7 and 8;.

Figure lll` is. aP Perspective. view of -the lower jaw o ftheaxlaclamp..

Figure 1`I isV airagmentaryvdetail seetionalview on line 'Il-H of Figure 8;

Figure 12 is aY detail s ectionalview. of; one. of

the windowsy latythe, front rface off the planetary carrier;

Figure 1:3 isan. elevation. oi" the front. face 0I the'planetary'carrieit with its. rollerbearings on the n'xe'd axle,v which latter is cross-hatchedfor clearness;

,Figure 1fiSiaperSpectiVevievrof the support for` the,` tool holding carriage, the support' being, radially and axially adjustable onthe front face ofl the planetaryl carrier relative.. to the lattersv axls;

Figure-i5 is a View on a larger scale in medial vertical sectionfthrougir the upper portions' of the mechanism oiLFlgure l'lif;l

Figure; 16` is aside eleva-donor the vadjustable tool holdingAAV carriage and its.` reciprocating tool holder; l

Figure 1'7 is an end elevation of the mechanism of Figure 16, showing the ratchet and pawl for actuating the reciprocating tool holder;

Figure 18 is a top plan view of the mechanism of Figure 16;

Figure 19 is a vertical sectional View on liner larly to Figure 1 thereof wherein 'the inventionv is shown complete, mounted j On 9g Valve casing I0, with the grinding toolv l2 in position for grinding the valve seat I4, it will Abe obvious that the grinding tool l 2isoperatedby an electric motor I6 through the mediumbf flexible shaft i8 whose outer flexible casing is rotatably secured at its motor end so that this,l casing as a-whole is rotatable. The motor I6, inYFigure 1,.is mounted on a hinged shelf 20Which may-be secured to the valve casing, as illustrated, orto any other convenient support. p Or the motor may be mounted directly onsuch another. support. .When the hinged shelf 20 isemployed, it may be adjusted and set at various angles relative tothe axis of the Valve casing for `azpurpose which will later appear, the' adjustment being accomplished by the. slottedbracket 22 through Whoseslot the thumb screw 24 passes for threaded engagement With a depending. ear 26 on the under side of the shelf. i :Tightening ofthe thumb screw clamps the bracket22 to retain the shelf in any selected angular relation to the axis `of-thevalve casing.

According to the invention, however, the power driven grinding tool I2` is caused totravel in a generally'v planetary'. course around the axis of the valve casing whose seat isbeing ground. For this purpose a planetary carrier 28 is rotatably mounted on a fixed tubular axle 30 which in turn is adjustably supported "on a plate 32` which is secured to the end of the valve casing but which might bemounted on any other convenient support. The axle 'is heldin asuit'able' clamp V34 which is pivotallymounted onplate 32 as at'36 and angularly adjustable by the slotted 'bracket 38 and thumb screw 40 similar to the adjustment for the motor shelfA 20.V By this means the rotatable planetary carrier 28 may be adjusted about the pivot 36 to bring itsjaxis into perpendicular relation to the plane of a surface which is to be ground. Y I

Mounted on the front face' of the planetary carrier 28 and radially adjustable thereon is a carriage supporting barr 42 extending outward from the carrier 28 in parallelism with its axis and'braced as at 44. A carriage'S is mounted on bar 42 and is'adju'stabl'e thereon', by .means of the universal clamp 48, both along and around the bar as well as angularly relative to the bar. The carriage 46` includes la reciprocating tool holder l50 wherein the stiff end portion I9 of the flexible shaft I8 may be clamped as at 52. The iexible shaft I8 conveniently is threaded through and supported by the tubular axle 3l),

` vThe planetary carrier 28 may be manually rotated, as shown in Figure 4, or maybe power driven asin Figures 1 and 2. l'I lie carrier is circumferentially grooved as at 54y for belt Ydrive,

from the relatively small pulley 56 which may be mounted on shaft 58 connected by reduction gearing 68 to the motor shaft, as in Figure 1, or shaft 58 mayhave a crank 62, as in Figure 4, for manual turning of the planetary carrier 28.

Figure 2 shows generally the same grinding mechanism of Figure l, but the carriage 46 is adjusted on bar 42 to bring the grinding tool l2 into proper relation to the valve seat in the disk valve type of casing there portrayed.-

Figures 3 and 4 similarly show grinding mechanisms comparable to that of Figure 1, Figure 3 having a special support for holding both the grinding mechanism and the gate valve which is being ground; and Figure 4 having the motor on the work side of the planetary lcarrier 28 for the grinding of a stern type of valve held in axle 3U as a chuck.

The foregoing general description in connection with Figures 1-4 shows the general utility of my improved grinding mechanism, and suggests the great multiplicity of types and varieties of grinding operations the invention is capable of accomplishing.

vThe structural' details will now be described` with reference to Figures 5-22,

Referring to Figures 7, Sand 13, the planetary carrier 28 may be a hollow disk or wheel whose circumferential belt groove 54 constitutes vit a pulley which may be belt driven as previously described. The front wall 64 of the carrier is shown integral'with its fgrooved periphery, and has window openings 66 therethrough in each of which is an insert 68 of a suitable transparent material, preferably a flexible material 'so that the inserts may be snapped into grooves l) as indicated in Figure 12.

The rear wall 'l2 of the carrier is represented as a removable plate secured in place by the screws 14. This plate wall also has window openings i6 covered by a disk 18 of transparent material secured to the plate by screws 80.1

The carrier is rotatably mounted on the tubular axle 38 by aroller bearing structure which is best seen in Figure 13. A four point bearing is illustrated although, obviously, a three pointv bearing will suffice. The rollers 82 are carried at the inner ends of arms 84 which are independently adjustable radially of the carrier by the screws 86 in their respective supporting blocks 88 mounted on the front face or the carrier.

Thus the carrier may be concentric with the axle (Fig. 9) in its under side for fitting the exterior curvature of axle 3U, and has a forward-projecting part 96 for extending through opening 88 in the rear cover plate l2 and transparent disk I8 of the carrier, terminating in the plate part lill), apertured at |82 for receiving the upper set of roller bearings 90. The rearward lextending portion of the upper jaw 92 has ear' H14 thereon on which the mounting plate 32 is pivoted at 3G. vIt has also a plate part |06 in whichthe thumb screw 4D threadedly engages in coasting with the slotted bracket 38, pivoted at -I08 von plate 32, for adjustablyclamping plate32 in adjustedposif emergen tions. This' upper jaw- 82Jof the-clamp isshown mtdetai-linyFigure 9.

v:The lower jaw-|510, of the' clampr has. .they con.. cavity |:|12. in Iits upper side `for fitting vthe-.enterica curvature of axle 30, andhas .forwardl projecting part ;-|f|4 extendingthrough the opening '981111 the carrier, terminating inthe plate part H6,

apertured at 1|v|8 for receiving athe: lower set kot roller bea-rings, 90. Detailsioof, this lower jaw are bestseenzn Figure 10.

The jaws 92, |0 .each has a seat.A |20,` for seating a clamping strap |22 which. may be .drawn tight around the jaws ,by ,means Yof the screws |24, |.26\ best seen in -Figu'reSL Mounted on theexposed face offrent wall 64 of vtheplanetary'carrier is aavertically adjustable plate |28V (FiguresA 'Z` and 14) .carryingat onefend thexri'ght-angularly v disposed: shelf al 30. Plate 28 has itsside edges bevelled asiat. |32 :for-v sliding adjustment in a complementally bevelled slide block |34 on the front'face of wall 64 olf the carrier. Wall 64 also has. anoutward projecting lug |36, and plate |28has a rearwardly projecting part |38 by means-of which plate |28maybe adjusted radially of the lcarrier through the medium of adjusti-n-gscrew |40which threadedly engages lug |36 of wall 641and.has: a,irotatable securement at its lendtothe part |38,.;of plate |28. f

Shelf l|30 has a bevelledaside wall; channel |42I in its upper face forslidably receivingthe adjustable block |44 whose-adjustment maybe accomplished by screw |46 .rotatably anchored in lug |48 on the shelf and'threadedly-engagingthe block |44. One end ofastiibar 42 is removably clamped in the block |44 by the. wedge and screw clamp |52 best .-seen in Figure 1 5,y and Kthe bar projects outwardly a considerablefdistance formounting the carriage 46 .andreciprocatingytool holder 50. Preferably bar 42 is braced by the brace rod'44 pivotally secured at one end to plate 28,;as.at |54, and adjustably clamped at its other end :to bar-46, as at |56. Carriage 46 is adjustably mountedat any vdesired location along bar42 bymeans offthe universal clamp 48.v vThe carriage comprises. a, yoke framehavinglthe parallel side. arms |58,` LEU-. connected by the bridge part |62.` Projectingfrom the bridge part vISZfare-the two spaced vears'l64, |66, each apertured .toreceive oneyof the-.clampingsleeves |68, |10. The sleeves are tubular'ior receivinga clamping boltV |12 headedatonefend to engage flange 69- of sleeve |68, and;threadedly engaging nut |14 at its other end fordrawingthe nut against Aflange of-sleeve |70. Theinner 'ends of the sleeves are spaced apart, and .each

isnotched as at |16 (Figs. 19, 22) to tthe exterior contour of bar 4 6 which vextends through the elongated hole |18 in bolt |12. When the clamp is loosened, the carriage is universally adjustable relativeto bar 42, and tightening of the clamp effectively secures the carriage in a selected position.

Journaled inthe arms |58, |60 of r the. carriage is a drive screw |80 having both right .and'left hand threads thereon. As illustrated in .Figure 16, each arm |58, |60 hasa cap bearing at its end for mounting screw A|80. A bearingportion of the screw at one. end projects outward beyond arm' |58 asA at |82, and a ratchet wheel |84 is xed thereon. Loose on this projecting. portion of 'the screw is a bell-crank'lever Whoseonearm |86 carriesk a spring pressed pawl| 88 which yis Vconstantly urged by its spring towardy theteeth v'has spring pressedengagementas at 2|4 (Figure 3 {8D-.af thematchet wheel; Thel teethorztheratchet .arefsuch `Ithat a clockwisemovement o'f the, bellcrankvand-'pawL-advances the ratchet wheel clockwisefa..distance:corresponding to one toothspace, .and the screw 80 isA :simultaneously rotated `an equalgamount.

'The other arm |02 of thebell-crank has connectedtofit, as ali-L94, one end of van actuating rod- |96 Whose other endhasr ahead |08engaging the lcam .end .200 of a-rocker arm 202 which is mounted` to lturn with short shaft 204 journalled in-bracket 20.6 onther bridge part |62 of the carriage. Actuatingfrodi |96 is maintained in operative relation: to lthe rocker arm 202 by a slidable engagement with. guiding -block 208 projeet'mg frcmarm, |fofthe1earriage, and ,by spring 2|0 whichaconstantly urgesxthe head |98 of the rod against. the campof the rocker arm 202. `Thus Ja counter-clockwise rotation of` rocker-arm I202 (Figure 16) depresses the actuating rod |96 and advances the yratchet wheel one tooth space in clockwise direction v(Figure 17). Spring 2|0 restores-the pawl .to its-position of Figure 17 as soon as rocker-arm 202.permits.'

Intermittent rocking movements of rockerarm.20'2 are accomplished through the'long lever 21,2 which, as seen in Figure 1, extends from a fixed connection to short shaft 1204, which ,constitutesl a pivot, -tol a location adjacent toy the outer face ofthe planetary carrier 28 `where ,it

' 7) with a .cam 2-'|6 xed onthe stationary Vaxle 30. rThe cam has a single high-spot 2|8 (Figure 13) whi'chrrockslever 2|2 andythe rocker arm 202 to. advance the-ratchet wheel once during each Arotationof the planetary carrier 28 Aabout theaxle 30and cam 216. The lever 2|i2 may be adjusted Ainleugth Vto suit any parti-cularoperating conditions, by having, it in/two sections releaseably clamped together as -at 220 in Figure 1.

`Itfvvill 4be obvious from the foregoing description that, regardless of where or how the. carriage 46 may'besetrelativefto supporting bar 42, each rotation` of`r planetaryycarrier 28 will result in onetooth-space clockwise .advance of ratchet whee1.|84' and a. corresponding slight vrotation of thescrew fin. the carriage.

The tool holder50jis mounted in carriage 46 for reciprocatory travel between the arms |58, |160. It' comprises a rectangular hollowyframe slidably suspended on` the-two parallel and spaced stii rack-rods 222,224. Within the frame are thetwo half nut members 226, 228 connected togetheracross screw Alllrbythe yoke 230. The half nui-,members and yoke are slidable as a unit withinthe frame-to bring one or the other of the half. nuts into'threaded engagement with the screw, the spacing being such that only one half,

nut 226 or 228 can engage the screw at any one time.v An opening 232 in the top wall of the frame permits vprojection to the exteriorgof a shift p in 234 connected to the yoke 230. Open-' the screw,;theintermittent rotations of the screw 4 bypawl |88 and ratchetwheel |84, cause intera mittent movements of the Itool holder 50 rst in onedirection and then in the opposite. direction along screw|80.

ReferringtoJEigures 19 and ,21, the halt nut and yoke unit 226, 228, 230 has a sliding bearing in the front and rear walls of the `hollow frame` of the frame, for actuating respectively the pawl levers 240, 242 pivotally mounted Vone at the front side and one at the rear side, (Figure 16)', of the tool holder frame. The pivot for lever 240 is a shaft 244 journaled in the long boss 246 (Figures 19, 20) forward and at the right top edge of the frame. Lever 240 is fixed to the forward end of shaft 244, and pawl 248 is fixed to its rear end for overhanging the frame and engaging the teeth rack rod 221 when permitted to do so. A spring 250 constantly urges lever 240 and its pawl 248'to rack rod engaging position. But when half nut 226 is in engagement with screw |80, the bevelled end 238 of half nut 228 will be projected as a cam into position to disengage pawl 248 as in Figure 16, holding it disengaged until half nut 228 is shifted toward screw engagement past a neutral position in `which both half nuts will be free of the screw |80.

Lever 242 is similarly mounted on shaft 252 which is journaled in the long boss 254 (Figures 19, 20) rearward and at the left top edge of the frame. Lever 242v and pawl 256 are xed at opposite ends of shaft 252, with the pawl in position to engage the teeth of rack rod 224 when the cam end 238 of half nut 226 permits. spring 258 urges lever 242 and its pawl 256 to rack rod engaging position.

When the tool holder 50 is connected for intermittent travel in either direction along screw |80, as'when half nut 226 is engaged With the screw, for example, a pawl and rack rod engagement prevents movement of the carriage in the opposite direction, as when the pawl 248 engage rack rod 222. Also, during the interval of reversal of travel of the tool holder, when both half .nuts will be momentarily disengaged from the screw |80, both pawls 248 and 256 will be simultaneously engaged with their rack rods, thus eliminating any chance of thetool holder accidentally sliding along the screw. As soon as a half nut engages screwA |80, the proper one of the pawls 248 or 256 will have been cammed free of its rack rod. f I

In Figure 19, spring-pressed balls 260 coact with depressions 26,2 in the half nuts to retain the half nut unit yieldingly in one or the other of its screw-engaging positions.

Reversal of the direction of intermittenttravel of tool holder 50 on screw |80 is accomplished l by the dogs 264, 266 (Figures 16, 19) respectively engaging the shift pin 234. The dogs are adjustably mounted on the parallel rocker shafts 268, 210 extending betweenI and journaled in the arms |58, |60 of the carriage 46.v The rocker shafts are geared together at one end by the meshing pinions 212, 21.4, as seen in Figure 19, and the left hand end of shaft 268 (Figure 16)" projects outward beyond the arm |60 and has fixed thereon the crank arm 216 (Figure 17) which is connected by link 218 to the work arm |86 of the ratchet-actuating bell crank lever. Thus each time the ratchet wheel |84 is advanced to rotate screw |80, the rocker shafts 268, 210 are rocked in opposite directions, shaft 268 clockwise and shaft 210 counter-clockwise. The dogs 264, 266 depend from their respective shafts andmay have the generally inverted L shape indicated in Figure 19, where dog 264 is shown in its positionafter having been rocked into shifting engagement with pin 234. Pin 234 is free of the dogs throughout But when the tool holder reaches a position on screw where shift pin 234 is opposite one or V.the other of the dogs, the next rocking of shafts 268, 210, and the dogs thereon, will cause that dog which is opposite the shift pin 234 to shift the pinand the half nut unit to bring a different half nut into engagement with screw |80. The tool holder 50 then travels intermittently in the opposite direction until pin 234 comes opposite the other dog and another reversal is effected. The tool holder 50 includes a clamp for'securely gripping the stiff end portion I9 of the exible shaft I8 at whose end the tool |2 is mounted. One jaw 280`of the clamp isrotatably adjustable on stud 282 projecting from the screw-surrounding frame rof the tool holder, and is adapted to be set in any selected position by the screw 284. This jaw 280 has spaced ears 286 through openings in which the shaft I9 loosely extends. The other jaw 288 of the clamp fits between the ears 286 and may be drawn toward jaw 280, to clamp shaft I9 between them, by the threaded rods 290 projecting in parallelism through holes 292 in the jaw 280, and having nuts 294 screwed tight thereon against the jaws 28|).y

Obviously the tool end of shaft |9 may be adjusted in the clamp 280, 288 to position the tool |2 at varying distances from the clamp. And the shaft may be set at various angles aroun stud 282 by adjusting screw 284.

As a measure of safety against accidental slip of carriage 46 along bar 42 when clamp 48 is loosened, as when the bar 42 is vertical or tilted, I provide the safety bar 296 (Figure 18) which has one end secured as by screw 298 to the head of clamping bolt |12, and has at its other end the yoke 300 which may be clamped around bar 42 by screw 302 as best seen in Figure 17. The

yoke may be clamped tight on bar 42 prior to loosening of the main carriage clamp 48, to hold the carriage at a. fixed location along the bar while the carriage is being otherwise adjusted relative to the bar.

In operation, my grinding mechanism conveniently may be carried to a ship or other location where a grinding operation is required-on a valve or valve seat, or other element whichv cannot be brought conveniently to a grinding machine.

It is a feature of the invention that my mechanism may be readily mounted on or operatively adjacent to a valve casing or other object having a surface or surfaces needing to be ground, as suggested in the showings of Figures 1 and 2 of the drawings. Or a special supporting frame 303, as in Figure 3, can support my grinding mechanism in grinding relation to work also held in the frame, such as the gate valve 304 shown suspended from screwy 306 and additionally sustained and braced by the rod 308.

In the arrangement .of Figures 1-3, and many others, the flexible shaft I8 will be threaded through the stationary axle 30, to avoid its becoming entangled during the planetary travel of its tool end.

In Figure 4, however, the axle 3|) is utilized as a chuck for holding the work, it having set screws 3| for engaging the valve stem as shown in the detail view of Figure 5. In su'ch case the motor is brought over to the work side as in Figure 4. A frame support 305, ink Fig. 4, is shown, mounting the carrier 28 with adjusting means similar to that `described in connection with Figs, 1 and 2.

'I u The planetary carrier `may be adjusted on axle 313". to be''c'oncerrtricV therewith or eccentric to varying degrees',`by adjusting xits arms 84 carrying' thesupportin'g rollers 82., Y"Also the carrier may be tilted' to various angles as suggested in Figures l and3.l n l Radial adjustment-ofbarjn'on which carriage 46 is mounted,toward or A,from the axle 30, may

be accomplished by. Screw' III-0 on the carrier. l

And'long'itudinal'adjustment of bar 42 and the carriage 46 toward or from the carrier 28 can be eiected by screw Ifl on the vertical slide plate |28.

These adjustments can be made by the operator while observing the tool I2 through the windows 16, 66 in the planetary carrier, to get precision adjustment of tool I2.

Previously the tool will have been adjusted to approximate precision setting by means of the universal carriage clamp 48 and the tool holder clamps 280, 288 and 284. Also the dogs 254, 266 will have been set to determine a proper reciprocating travel ofthe tool holder 50 in carriage 46.

The mechanism thus is adapted to serve practically every grinding situation, a suitable kind and style of tool I2 being selected for particular riage 4B, to `prevent foreign matter interfering with a proper operation of the tool holder 50. In Figure 16 I show such a protective cover comprising the two flexible tubes 3I6, 3I8. Tube 3 I6 is connected at one end to arm |58 of carriage 46 and at its other end to the tool holder 50. Tube 3i 8 is similarly connected at one end to arm |60 of the carriage and at its other end to the tool holder.; A light coil. spring 32D may be mounted interiorly of each tube maintaining the tube walls out of contact with the screw but permitting the tool holder to travel in either direction with an accordion-like collapsing vof theutube toward which the tool holder is moving.

Although the invention is illustrated and de-A scribed in connection with grinding operations, it will be apparent to those skilled in the art that my improved mechanism may employ atool other than a grinding wheel, and thus the featuresbf the invention may be used for various operations outsideof the eld of grinding.

I claim as my invention:

1. Grinding mechanism having a` rotatingr grinding tool, a drive shaft andl power means therefor, lcombined with a rotatable carrier havf Aing a rigid bar projecting from its front side in parallelism with its axis and at a radial distance outwardy from its axis, a carriage on said bar, the carrier and carriage being relatively adjustable along the bar,` and the carriage being adjustable around the axis of the bar, means for securing the carrier and carriage relatively in adjusted positions, means on said carriage hold-` ing the work end of the drive shaft, means at the rear side of the carrier for supporting the carrier rotatably, and means for rotating the carrier to move the rotatingftool through an arcuate course.

2. Grinding mechanism having a rotating grinning;v tocljanrive shaft and power means therefor, combined with@ rotatable'Icarrierhavingv a rigid bar projecting from, its'fro'nt lside in parallelismlwth 'its' axis and ata radial distance voutward froml Iits "axisl a lcarriage'adjustable Aalong and aroundsaid bar including a clamp forxing lit on the bar 'in adjusted positions, ,a toolnholder in said carriage'clamping the work vend 'of 'the said drive shaft, meansuprojecting'at 'the Arear side of Ithe carrierffor' supporting the 'carrierrotatably, andmeans for rotating the carrier to move the rotating tool through an arcuate course.

I 3. Grinding mechanism having a rotating grinding tool, a flexible drive shaft and power means therefor, combined with a rotatable carrier and a support therefor; a carriage mounted on the carrier radially outward from the axis of the carrier; a tool holder'in said carriage holding the work end of said drive shaft at a location remote from said power means; means for rotating said carrier tomove the rotating tool through an arcuate course; and means associated with the carrier and carriage for intermittently shifting the position of the tool holder and rotating tool relative to the carriage in response to rotation of the carrier. j

4. Grinding mechanism having a rotating grinding tool, a drive shaft and power means therefor, combined with a rotatable carrier and a supportxtherefor; a carriage mounted on the carrier radially outward from the axis of the carrier; a tool holder in said carriage holding the work end of said driveshaft; means for rotating said carrier to move the rotating tool through an arcuate course; a screw in said carriage threadedly engaging said tool holder; a ratchet connected to the screw; and ratchet actuating means responsive to rotation of the carrier for intermittently rotating the screw to move the tool holder and rotating tool intermittently along the screw.

5. Grinding mechanism having a rotating grinding tool, a drive shaft and power means therefor, combined with a rotatable carrier and a support therefor; a, carriage mounted on the carrier radially outward from the axisvof the carrier; a tool holder in said carriage holding the work end of said drive shaft; means for rotating said carrier to move the rotating tool through an arcuate course, a screw in said carriage threadedly engaging said tool holder; a ratchet connected to the screw; and ratchet actuating means responsive to rotation of the carrier for intermittently rotating the screw to move the tool holder v l and rotating tool intermittently along the screw; and means for reversing the direction of travel of the tool holder and'rotating tool on the screw.

6. Grinding mechanism having a rotating grinding tool, .a drive shaft and powermeans therefor, combined with a rotatable carrier and a support therefor; a carriage mounted on the carrier radially outward from the axis of the carrier; a tool holder in said carriage holding the work end of said drive shaft; means for rotating said carrier to move the rotating tool through an arcuate course; a screw in said carriage threadedly engaging said tool holder; a ratchet connected to the screw; and ratchet actuating means responsive tov rotation of the carrier for intermittently rotating the screw to move thetool holder and rotating to'ol intermittently along the screw;

anda longitudinally 4expansible and contractible flexible protective covering connected to the carriage and tool'holder and enclosing the screw.

7. Grinding mechanism`4 having a rotating grinding tool, a 4drive shaft and power means therefor, combined with a rotatable carrier having means radiallyoutward thereon adjustably holding the Work end of the drive shaft; an axle rotatably supporting the carrier and itself free from rotation, said carrier being hollow, and lthere being thrust bearings in its hollow, and the carrier having radially adjustable roller bearing suspension on the axle. y

8. Grinding Vmeczhansrn having a rotating grinding tool, a drive shaft and power means therefor, combined With'a rotatable carrier having means radially outward thereon adjustably holding the Work end of the drive shaft; an axle rotatably supporting the carrier and itself free from rotation, and mounting means for said grinding mechanism independent of said axle having vprovision for mounting a piece of work thereon in grinding relation to the grinding tool.

WALTER A. SHANLEY. 

